1. Field of the Invention
The present invention relates generally to a storage media interface and, more particularly, to a storage interfacing method and apparatus that enables different kinds of storage devices to share a bus though a MultiMediaCard (MMC) interface.
2. Description of the Related Art
An advanced mobile terminal includes a call processor and an application processor or a single call/application processor. The call processor is used to process base communication functions related to phone calls and messages. The application processor is mainly used to process and control various supplementary functions related to a camera, multimedia, an electronic dictionary and the like. The mobile terminal further includes a plurality of mass storage devices to store voluminous multimedia data such as music files, photographs and moving images. For example, a NAND flash memory is used as an internal mass storage device. A Secure Digital (SD) card or MultiMediaCard (MMC) card is mainly used as an external mass storage device. Individual mass storage devices are connected to the application processor through separate storage interfaces.
FIG. 1 illustrates a conventional storage interfacing apparatus 510 using NAND flash technology for a mobile terminal.
Referring to FIG. 1, the storage interfacing apparatus 510 includes first and second control units 511 and 515, respectively, serving as a call processor and an application processor, respectively. The second control unit 515 is connected to a NAND flash memory 525 through a NAND interface 521, and to an SD card 531 through an MMC interface 523. Under the control of the first control unit 511, the second control unit 515 has access to data stored in the NAND flash memory 525 and the SD card 531. The second control unit 515 includes a NAND flash memory controller and an SD card controller. For data access, the second control unit 515 is connected to the NAND flash memory 525 via a bus, and to the SD card 531 via another bus.
In the storage interfacing apparatus 510, the second control unit 515 does not simultaneously access the NAND flash memory 525 and the SD card 531. Separate storage interfaces for the NAND flash memory 525 and the SD card 531 may cause an increase in both the number of pins and the size of the second control unit 515.
Recently, a new NAND flash memory supporting an MMC interface has been introduced as a high-speed mass storage device. However, the conventional storage interfacing apparatus 510 does not provide an interface between the new NAND flash memory and a different mass storage type.
The above problems may be common to other device-specific interfacing apparatuses, and to other control units controlling and accessing different types of mass storage devices.